Water-tube boiler



June 11, 1929. E, A, FIELD 1,716,770

WATER TUBE BOILER Filed April 27, 1927 INVENT EdWflPd /Z Fl'e Patented June 11, 1929.

UNITED STATES "PATEN 1 T' orrlcsz EDWARD A. FIELD, or cnrcaeo, ILLinoIs, ASSIGNOB T Dancer-F rth coQfoF CHICAGO, rumors.

'WATER-TU'BE BOILER.

'1 Application filed April 27, 1927- Serial No. 186,927.

The main object of this invention is to pro vide an improved water tube boiler which is highly eflicient, may be readily cleaned, has no baffle plates and no horizontal surfaces for the collection of soot and scale, and one in which the tubes are not likely to become clogged with scale or sediment.

A further object is to provide a structure having these advantages which is very economical in its parts and one in which the parts can be readily assembled and disassembled,

particularly in the matter of tubes, as occasion may require.

Objects pertaining to details and economies of my invention will definitely appear from the description to follow. The invention is defined in the claims.

A structure embodying the features of my invention is clearl illustrated in the accompanying drawing 1n which:

Fig. 1 is a side elevation partially in central longtudinal section on line 1-1 of Figs. 2 and 3.

Fig. 2 is a transverse section on line 22 of Fig. 1. Fig. 3 is a fragmentary plan view partially in horizontal section on line 33 of Fig. 1. In the embodiment illustrated, I provide a base designated generally by the numeral 1 having an ash pit chamber 2 at the front and a smoke box chamber 3 at the rear. Thegrate 4 illustrated isof a standard type.

The outer shell designated generally by the numeral 5 and inner shell designated generally by the numeral 6 are arranged in spaced relation to provide a water chamber 7 sur- "rounding the inner shell. This inner, shell comprises downwardly diverging firebox wall portions 8 and vertically disposed combustion chamber side wall portions'9 connected by the outwardly inclined tube. plate portions 10. The crown sheet port-ion 11 hasa central horizontal portion 12.

. A bridge wall plate 13 is arranged to project above thesmoke box 8 providing a down passage 14 at the rear of the combustion chamber. The bridge wall 15 is formed of fire brick, the wall plate 13 being preferably slightly inclined and shouldered to receive and effectively support the brick. The tubes 16 are all vertically disposed and angledas illustrated,

The top portions 17 of thesetubes are disposed through the horizontal portion 12 of thecrown sheet and at right angles thereto. The bottom portions 18 of these tubes are connected to the tube plates 10 and'disposed at right angles thereto.

This form of side walls of the inner shell provides an enlarged water space at the bottom extending the length of the boiler on both sides which insures an ample supply of water to keep the tubes filled at all times, and thus promoting rapid circulation throughthetubes which prevents foaming and increases the'efficiency of the structure.

I The outer shell is provided with a plurality of plugs 19 in the top thereof and a plurality ofplugs 20 in the side walls thereof, each plug being disposed ina centered relation relative to a group of the tubes, commonly a group of four, so that all of the tubes of the group are accessible through the one plug scribe certain modifications or adaptations which I contemplate as I believe the disclosure made will enable those skilled in the art to embody or adapt my improvements as may be desired.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. In a boiler, the combination of a base provided with an ash pit chamber at the front and a smoke box at the rear, an outer shell, an inner shell spaced therefrom. to provide a water chamber surrounding the inner shell, said inner shell comprising down-' wardly diverging fire pot wall portions, vertical combustion chamber side wall portions I connected to said fire pot wall portions by outwardly inclinedtube plates, and a crown sheet having a horizontal central portion, a

plurality of vertically disposed angled water tubes having top port-ionsdisposedat right anglesto the horizontal portion of the crown sheet and bottom portions disposed at right angles to the said tube plates, and a bridge wall disposed at the rear of the fire box and providing a down passage at the rear of the combustion chamber communicating With said smoke box.

2. In a boiler the combination of a base provided with an ash pit chamber at the front and a smoke box at the rear, an outer shell, an inner shell coacting therewith to provide a Water chamber and extending over said smoke box, a plurality of vertically disposed angled Water tubes having their upper ends connected to the-crown sheet of the inner shell and their lower ends connected to the side Walls thereof, said inner shell and said tubes being continued over said smoke box, and a bridge Wall disposed at the rear of the firebox and providing a down passage at the rear of the combustion chamber communicating With said smoke box.

In Witness whereof I have hereunto set my 20 hand. a

' EDWARD A. FIELD. 

